John browning executor of said john m



J. M. BROWNING FIRING CONTROL FOR AUTOMATIC MACHINE GUNS 3 sham-sheet 1 FiledJuly l, Q24.

J. M. BROWNING FIRING CONTROL FOR AFJ'IfOMATIC MACHINE GUNS Filed July 14. 1924 s ShetsQ-Sheet 2P J. M. BROWNING FIR LING CONTROL FOR AUTOMATIC MACHINE GUNS Filed Jul-y 14. 1924 s Sheets-Sheet 3 fm entar' a;

h p atented May 10, 1927 Y UNITED-1 STATES;

QA N OFFICE,

' JOHN M. BROWNING, or oonnn', UTAH; zronnnnowmncnxncuron or SAID JOHN m.

nnownm ypncnnsnn.

, Trams oon'rnoL j bniitq am c' MACHINE Guns.

Application fil ed. July 1;,

The invention relates to a firingcontrol; o. tlie'breechcasing. the fixed part of the for automatic niarhine guns and moreflpan ticulnrlv to such a'control 'tor guns adapted also :1 portion of the breech block within the 'to be mounted on aircraft to tire through the 1 plane swept by the blades of the airplane propeller.

It is an object of the invention to provide such a control which is simple in construe: tion and light in weight, yet reliable in oper-i ation and most durable. \vhichcan be readily adjusted and adapted to fit it for use with different'types of airplanes, and for changes in the relative location of the gun and the power unit of the airplane, and which adapts, the gun to be, atv will, fired in synchronism with the rotation of the propeller or at its normal rate whenfiring automatically.

Other and further objects will appear as the description proceeds. I

These objects are attained by the provision of the novel improved-means now to be clescribed -in connection with the accompanying in the claims appended hereto.

In the drawings:

Fig. 1- represents in side elevation a-portion of the left-hand side of the breech casing -ot' an automatic machine gun showing drawings. and more specificallvpointed out.

the invention applied thereto; parts of the.

impulse transmitting broken away.

Fig. 2 represents in a front view a portion of the impulse transmitting system. Fig. 3 represents a rear view of a portion of said impulse transmitting'system showing system: having beenits co-operative relation with the impulse] generating. means. i

the portion of the transmission system shown in Fig. 3. and on its natural scale, the

inoperative positio hand side view.

fixedly secured to the breech casing ofa by, respectively, in a front view and in aleftf Fig. 7 represents a plan view of a portion of the gun with the invention applied theregun and through showing the breech block in elevation and .the section being of Fig. 7. v impulse transmitting rod belpg shown in its fdetaclied.

In the drawings, the invention is shown npplied .to anantomatic machine gun of the lass shown in my prior 192 4. Serial no. 725,868.

ranie ot the trigger mechanism unit, and

breech casing being shown in a section taken onfltlie line 77 of Fig. 10; the parts are shown in their inoperative position for synchronized firing.

. 11 Fig. 8 represents a vertical transverse section on the line 8-8 of Fig. 9, as seen from the rear. tln-ou h the breech casing of the the trigger mechanism unit,

in its forward firing position, and the parts of the tiring mechanism in the position they occupy the instant the sear is released; the lower portion of the gun and a portion of the cooking lever are broken away.

Fig. Qrepresents 'a portion of the breech casing of the gun and of the firing control as seen from the left and in a vertical lon ittidinnl section on the line 9-9 of Fig. 7; t 0 parts are shown in their-inoperative position for synchronized firing.

Fig. 10 represents a vertical transverse section through the gun on the same plane as Fig. 8,'the parts'of the firing mechanism being shown in their inoperative position for synchronized firing.

Fig. 11 represents in a left-hand side view .the rear portion of the breech block and parts carried thereby, thev rear portion of the firing pin'being shown in dotted lines in a central. vertical longitudinal-section and held in-a rearward cocked position by the cocking lever.

Fig. 12 represents'the breech block and I L v parts carried thereby in a rear view. Fig. 4 represents a sectional VIQWihIOUgll. I

Fig. 13represents a view similar to Fig. 9, taken on the line 13-13 Fig.' "l4 represents a perspective view of the trigger lever actuated bythe impulse transmitting means, detached.

Fig. 1-5 is a similar view of the connector,

detached. mm. detachethand with parts carried theref Fig. 16 is a similar view of the sear catch,

Patent No. 1,293,021

I on the cam shaft 2 for automatic machine gun, dated February 4, 1919, but it will be understood that certain features thereof are equall applicable to other classes of automatic mac ine guns.

- For convenience of description, the means forming the preferred embodiment of the invention may be divided into three units, namely, '(1) the impulse generating and transmitting unit, (-2) the trigger mechanism unit, and (3) the breech block unit.

The impulse generating and transmitting unit comprises means whereby the trigger lever 6 of the trigger mechanism unit is oscillated in synchronism with the rotation of the propeller ot' the aircraft upon which the machine gun is mounted. The impulses are preferably mechanically transmitted from a cam shaft 2 suitably mounted on the motor 1 of the aircraft and carrying-a cam sleeve 3 having two opposed ram projections 3. The cam sleeve 3 is preferably adjustably secured to the end of the shaft 2 thereby permitting the proper angular positioning of the cam projections 3 with relation to the propeller blades. To keep the cam sleeve 3 securely in its adjusted position, it is providedwith line teeth 3 adapted to interlock with corresponding teeth on a col lar .2 on the shaft :2, see Fig. 1. A castellured nut 4 screwed onto the correspondii'ig end of the shaft keeps the said teeth in engagement with each other and the nut is locked b suitable means, such as the cotter pin 5. by this construction, a tine ad ustment of the cam sleeve 3 relative to the shaft 2 can be readily made.

In the embodiment of the invention selected for illustration, the trigger lever 6 is rocked on its transverse pivot pin 6" in one direction by a strong helical spring .6, see Fig. 9, but to move it in the opposite direction against the tension of said spring, impulses generated by thc'cam pro ections ii are transmitted to said lever bya pair of push .rods 7, 8 of small diameter-land an intermediate nockerjt), see Figs. 1 and 9. The rods 7, 8 and the intermediate rocker 9, while relatively light and consequently having little inertia, are yet capable of transmitting a considerable thrust, and are, because of their lightness, readily returned, after actuation by'onc cam projection 2, into position for actuation by the next. cam projection 23 by the spring (3". The end of the rod 7 adjacent the cam sleeve 25 has an enlarged portion 7 having a rounded end which normally projocts'bn. yond the fare of a bracket 1,0 secured to the rotor l by any suitable means such as the screws 10, see Fig. 3, into the path of the cam projections 3 (see Figs. l and 3). The opposite end of the rod 7 engages one arm 9 of the two rigli't-angularlv arrangml arms of the rocker 9, while the-adjacent'end of the rod 8 rests against theotlun'arm 9" of the rocker. The other end ofthe rod 8 normally rests against the trigger lever (i, see Fig. 9. By this construction i'or each rotation of the cam shaft 2 the trigger lever (i will be oscillated twice.

To prevent the relatively li ht rods 7 and 8 from bending or buckling, they are guided for the greater portions of their lengths by the spacing tubes 11 and 12,'respectively.

The tube 11 has one end secured as by screw threads, see Fig. 4 in the bracket 10 while its other end is adjnstably secured, as by clamping means comprising a split clamping element 13, and a' bolt l3, to a suitable bracket 14, which may be detachably secured to some part (not shown) at the tor of the aircraft, as by the bolt 1-t.' The form of this bracket and the manner of its connection to the aircraft motor will vary with the type of motor used. The adja ent end of the tube 12 is likewise adjustahly secured to the bracket. it by a split clamping element 15, and a bolt 15, and the. rocker 5) operatively connecting the rods 7 and 8 is also pivotally' mounted on said bracket on the pivot stud 9". The surfaces of the arms of the rocker engaged by the rods 7 and 8, if extended, would intersect in the axis of the pivot stud 9. The end of the tube 12 adjacent; the trigger mechanism unit of the gun is secured in a block 16 lilting between thc brecch casing and the forward portion of the frame art it ol' the trigger mechanism unit, sec 7. and said block is rclcusably secured to said part ll of the trigger mechanism unit by a spring actuated stud 17 on the blot-k 16, which projects into a corresponding hole 24 in said portion of the frame of the trigger mechanism unit,

see Figs. 1, 7 and 13. By inserting the l bullet end of a cartridge or other suitable tool in said hole, the stud 17 may be pressed back to permit the gun with the trigger mcchnnisnrumit thereon to be dis-connector from the impulse transmitting relative longitudinal parts.

.The foregoing construction provides a highly Hexiblc system of transmission from the cam shaft 2. to the trigger mechanism unit mounted on the gun, such flexibility adapting it for use with guns mounted in various positions with lelation to the cam shaft driven by the aircral'tmotor. Moreover, such flexibility is attained by the present construction without the incouvemcm-c inherent in all llowdon wire or cable transmission systems of making :uljustuients from time to time to allow for the stretching of the wire or cable. '.'The means whereby the transmission system may be readily detached from the trig-- ger mechanism unit on the gun, permits ol' the teady dismounting of a gun from the aircraft and the substitution of another movement of said system by 1 without necessarily disturbing thefladjust l ments of the transmission system.

transmission system involving-two ash rods will be understood thatthe 'iods'niill b arranged at the'angle necessitated by th particular installation and in some cases only a single rod extending from the cam shaft to the trigger mechanism unit will be required. In such cases, the cam projections and cam shaft are an arranged withrelation.

to the gun, that the cam projections will "be in'a position adjacentthe axis of the gun,

so that the d can be arrangedsubstantially parallel to said axis as'ist-hc rod 8 in the embodiment of the invention shown.

".lo minimize friction between the inner surfaces of the spacingtubes 11 and 12 and diameter than the rods '4 and 8, "and said bore is provided, at intervals sufliciently close to picventbending or buckling of the l'ods, with supporting and guiding bushings 18 for the rods. These. bushings, one ofwhich is shown in Fig. 4, are held in place by frietional engagement with the wall of the tubes orby any suitablemcans.

When the gun is not being fired in synchrouism with the propeller of the airplane;

19. see Fig. 4. which is fixed in the tube by. suitable means, such as the pin 19"pa. sstn, ,g' thiough a hole-in the tube audhaving a part thereof seated in anfannnlar groove 19 in said bushing. A reduced end 19 of this bushing is surrounded by and has fixed to it the cud ot' ahelical spring 20, the other end of which surrounds and is fixed to a cor- 'rcspondingly reduced part"?! at the inner end of the enlarged portion 72%, the rounded end of which co-op'erates with the cam pifo jections 3. This spring2Q constantly tends to withdraw said end of the rod 7 into its ii'ioperative position showxrin Fig.4, but is opposed. when the gun is being 'fired in synchronism with the rotation oit the propelli-r of the aircraft, by the strong spring 6" of the trigger lever; which renders the weaker sprin 20 inoperative for this-purpose. However.'whenthe firing control of the invention is renderedinoperative for synchronized firing by the means to behere-.

' iilat'ter described. the 'Splillgti is renderednopcrative and the spring 20, being unop need by the stronger spring, moves the rod- Y 'toihe position shown in Fig. 4, where its arranged at rightangles to eacliiibtherpit movement, of said parts. gitudm'al movement is limited, however, by the engagement of a spring-pressed stud 23 the rods 7 and 8. respectively, the bore of 1 each of HtlltLttlbOS is, of considerably larger 'anism carri lend is withdrawn from the path of thecam project-ions'll on the cam sleeve 3. The movement of the rod 7 is limited bythe through ja groove in the enlarged portion a 7 of sai'd rod, see Fig. 4. While I have hereinbefore described a" v secured to the left-hand side plate 21 of the breech casing of the 1111, as by the bolts The trigger mechanism unit is detachably 22, see Figs. 1 and 9. his unit is shown as compiising'two' frame parts 23 and 24, the part 23 being rigidly fined to the breech casing 21 by the bolts 22 and the part 24 being connected to the part by a longitudinally extending T-slot and groove connection which permits relative longitudinal Such relative lonon oneof-said' parts, as 23, see Fig. 5, .With a corresponding groove 24 in the part 24, shown in dotted lines in Figs. 7 and 9. The mechanicaltransmission system is connected in the movable part 24 of the trigger mechanism unit by the means hereinbefore described.

This limited movement between the parts and 24, allows'for the vibration or kick of the gun during the tiring. Since the trig- .ger lever '6 is mounted on a transverse pivot pin 6 in the movable part 24, by this construction the distance between it and the motor of the aircraft cannot vary re ardless of the longitudinal vibration of tie gun,

"which is necessary for the proper timing of the shots. This limited movement between the paits 23 and 24 also permits the substitution of one gun for \othehltv ithout necessitating any adjust me s in theiIQ-ausmission system.

As is learlysho in Fi s. 9 and 14. the

trigger lever 6 hasTls tsvfi arms (3" and 6 arranged substantially att gight. angles to each other and ofi'set along the. pivot, the arm (3 extending in a substantially vertical direction and being engaged neatts lower end ,iind on its forward face by the rear end of thoI'piish-rod 8. of the transn'iission system, gaud on its rear face by the forward end of the. helical spring (3 seated in a recess in the 3 frame part-.24. see 'Figs. 7 and 9: the other 'arm (i -extends rearwardly substantially horizontally and is, adapted to engage the outer -arm of the connector 25, pivoted on a lon -itudinalltv extending pin 25" in a transverse slot. in the frame part 23 of the trigger mechanism' unit, to lift said arm and thereby depress the inner arm of the connector. which projects through a slot in the side wall of the. breech casin to operate the tiring mechby the breech block unit. The trigger lever arm 6 has a long curved bearingsu'r faco 6 for operative engagement with {the connector 25 regardless of tho longitudinal vibration of the gun and consequent relative movement of the parts 23 and 24 of the trigger mechanism unit.

The connector 25, showndeltiil hed in Fig. 5,,rs 'normallykept on its m mt pin and swung to its inoperative osition by a spring 25 seated in a recess in t e part 23 and harmg one end thereof hearing against a noet-tion 25 on the member helow'itspivot 5 while its opposite end rests against an abutment. 25" projeeting forward from the rear wall of thelransverse slot inithe frame part 23 and provided with a' groove to receive the end of said spring 25 and therebykecpit H in dare. see Fi s. 5 and 6.

the outer end of the connector and naivestho same to the position shown In Fig. 8, where;

' as well as pivotal movement When the trigger lever 6 is swung on its pivot pin 6" by the rearward movement of the rod 8 its rear\'.'ardly extending arm engages the downwardly otl'set portion 25' at.

it is representtul as having just. released the tiring mechanism on the. breech hloektli to fire a shot. The eonneetor 25 has endwise for reasons which will now be described.

After tiring, thelireerh blot-k 2Z3 rel-oils in theusual ,manner compressing the, reaction s n'ing'iztl". ln suelr reeoil. a eamsurfaee 26 at the left-hand side of the'br ee blovk 26 engages the inner end of ,the-eonnei-torzlfi aml moves it. endwisefoutwardly rlight-ly beyond the. iosition shown in Figs. 7 and It). with the(lowmvardly ofi'set portion 25' outside the path of the rearward arm of the.

til

tive emmertitm between the trigger trigger lever 6. thereby breaking the opera- -e\'el' and the rennet-tor .25.

'lhe synehronized tirinpgmay be started or in the airrrat't by means oi a stop leverli' whieh is pivotally supported on a t-rimsvrrse pivot pin 27' in a vertieal slot in themovable frame-part. 24. see Fig. 9. This lever 27 is normally moved to and held in its operative position wherea shoulder 27" on its upward and rearward extending arm 27 engages lllh' der the end of the rearward trigger lever arm ti and lot-ks the same In the. raised position as :hown in Fi it. The means for s-o moving said'stop lever to and .holdingit.

- in its operative position comprises a strong helieal spring 27" seated in a vertieal rerrss in the bottom of the frame part 24 and beariug with its lower end against the short forvardly extending arm 27 of said stop lever. \Vhen thetrigger lever 6' is in the position shown in Fig. 9. its real: arm (3" is raised above the downwardly offset. portion '25 of the connector 25 and. by .itseng 'r with the vertiral shoulder formed by said oli's'et, keeps said eonneet-or in its outer position. i

The rearward arm 27 of the stop lever 27 is provided with an eye. 27" to whieh is seeured an operating eahle 28. see Fig.- 1, or other suitable means leading to the operators position. A pull on this eable swings the lever 27 about. its pivot. and withdraws .the stopshoulder 27 thereon,from'heneath ing and transmitting means hercinbefore described, and thus starting the synchronized tiring. If the stop lever 27 is held in its inoperative position, the sym-hronized living will eontinue as long as auununition is supplied to the gun.

\Vhen it is desired to stop the sym'hronim-d tiring the, stop lever 27 is released to the artion of its spring 27", which, it Ihe'reul' arm (3" of the trigger, lever ii is in the raised position, swings the ram surface 27 innuediatelyforward of the looking shoulder :37 and merging thereinto, against the under side of the end of the lever arm ti" and raises the same slightly higher until the looking shoulder 27" struck substantially on a curve l'rom the pivot. axis of the lever 27 moves under said end and thereby looks the lever- 6 in its ino ierative po=ition shown in Figs. 9 and lo. I the rear a'rm ti" of the trigger lever is in its lowered position when thqstop lever is released. the substantially vertieal portion ot the upward and rearward arm 27" is tirst lit) inoperative position. the eonneetor 25 is moved ontwarzl by the ram snrt'aee 26" on the lneet'h blot-k from the position shown in Fig. 8' until the downwardly ollsetportion 25' at the outer end of the ronnertor moves beyond the trigger lever arm (3. thereby permitting ,the spring 25" to return the conneetordo the position shown in' Figs. 7. 9 and It), where it is kept in an outer position by the. engagement of the shoulder formed by the downwardly otl'set portion 25' with the outside snrt'aee ot' the raised trigger lever arm 6", h

In order that the gun may be tired automatic-ally, when desired. as for-example, when the same is dismounted from an air eraft and used as a ground gun, the connet-tor 25 is in position for operatively engaging the firing mechanism on the breeeh lllfllk even when in its outer position shown in Fig. 10. and by depressing the inner arm and holding it depressed. as shown in Fig. 8. the gun will be tired automatically. To this end. the invention provides a trigger mechanism unit having in addition to the trigger lever operated for-synehronized fir:

ing. a 1nanually-operated means for moving lit) v the transverse pin 6", which forms also the pivot pin ofthe trigger lever 6, and having- -a vertical arm 29" formed with a finger piece means may comprise a manually operable trigger 29, see Figs. 1, '7 and 13, pivoted on at its lower end and a horizontal arm 29 extending under the outer end of the contor is formed at its inner end at the'rear' ncctor 25. 'A-spring 2'9 seated in a longitudinal recess in the part 24 and bearing with its forwardmndagainst the vertical arm 29" of the trigger-29 serves to keep it shown in Fig.8 to fire ashot. The connecwith a forwardly and downwardly inclined ca-m surface 25 which operates the firing mechanism on the breech block 26 as the.

same nears its forward irin position, if the P [trigger 29 is held back and t e inner arm of.

the connector :25 is thereby kept depressed,

thus continuing the fire automatically as" long as the ammunition is supplied to the, gun.- p A coverplate 23 is rigldl secured to the top of the laterally widene portion of the frame part 23 of the trigger mechanismunit by suitable means such as the screw'23", see Fig. 6.- This plate hasa clearance roove cut-in its underside to avoid inte erence:

\\'ith the movements of the outer armor the connector 25, see Fig. 8. r Y r The two frame parts '23 and 24 may readily disassemblcd'by bringing" the sprin -21- pressed stud 23" on part 23 o posite who e f 24 in the part. 24;, said hole being ofslightly' smaller diameter than said stud, ahd then 1 pressing said stud back so as to withdraw it from the groove 24" by inserting the bullet end otncartridge.oigother tool into said hole-f. The part 21 may then be'slid oft the part 23 in forward direction.v The parts are reassembled by procecding n the' reverse' order.

main springBO, the'rear end of which The firing mechanism onthe breech block may comprise the usual longitudinally movable firing pin 30 seated .in a longltil mal actuated in forward firing directionf'by the against a vertical abutment pin 31 'eirtend ing through a vertical slot in rear portlon of b the cocking lever 32 pivoted onthe' trans "(-vv A shouideron its lower arm with a shoulder on said tiring pin untii, in'the list of the for-T ward movement of the breech block; the cocking lever is moved to its .inoperat1ve, pinto'be thrown forward to fire a shot.

1 trigger mechanism.

I gage under a shoulder pm. which l'ioldsgthe firing'pin in "cortical. p rtion by, the engagement. of a position in the usual manner. After the release of the firingpin by the cockin lever, the firing pin moves" forward a sligit distance until it engages the sear 33, and is thereby held cocked, until released by the H To provide an easyrelease of the firin pin, the verticallysliding' sear 33 moun in a corresponding seat at the rear of'the breech block 26 is not provided with the usual square shoulder for on aging a corresponding shoulder formin t 1e rear wall of the cocking notch on the ring pin, but has instead, a forwardly and upwardly inclined shoulder 33*, Fig. 11, for engagement with a corresponding shoulder 3O on the firin pin, Thescar ismoved to itsraised position, as usual, the's ring arm 31'. extendmy; rearward-p rom t e upper end of the abutment pin '31 and having its rear end en- 33 at the upper, end of the sear.

By this construction it will be seen that the sear-33 alone' .o rnnt hold the firing pin cocked, the mam-fspring 30 tending. to

force-the sear down to release the. fin'ng pin because of the action of the inclined surfaces on the firing pin and sear, respectively.

The seal is held raised in its operative position against this tendency by a sear catch 34 shown, detached, in Fig. 16, and in assembled position on the breech block in Figs.

7, 8, 10, 11 and 12. This sear catch 34 comprises a two armed lever pivotally supported on its integraltrunnions 34* in correspond ing; seats provided therefor and extending longitudinally of the breech block, see Figs. 8,10, 11 and 12.

On its'left hand side the sear 33 is provided with a notch having a shoulder 33 at ,its upper end. struck on a curve with the axis of the trunnion's of the sear catch as a radius. The inncrarm 34 of the sear catchhus a correspondingly curved locking shoulder adapted to be swung under the shoulder on the scar to keep the same in raised position. A small helical spring 34" seated in a vertical seat in the breech block ,and hearing at its upper end against the seat on the breech block, see Fig. llfandflbuter arm 34 of the sear catch 34 tends to more the same to its operative position.

f-QQ-When the breech block is in its forward firing position, see Figs. 7, 8 and 10, the end (of the inner arm of the connector 25 is 10- the tiring pin and the forward end bearrngi against a shoulder. o'nthe firing pin,-'not' shown. Thev firing pin is moved to-the'" cocked position shown in Fig. 11, as usual,"

cated above theend of the outer arm of the sear catch 34, so that when said connector arm is depressed, the sear catch is-swung to gwithd'raw the curved shoulder on its arm 34 i from beneath. the corres onding shoulder surfaces 33 and 30 on the scar and firing pin,r'espectively, thus permitting the firing eases": p

On the subsequent recoil of the breech olock the firing pin is moved to the cocked position by the cocking lever 32, the sear returned to its raised position by the sprmg arm 31, and the sear catch 34 is swung to its operative position with the end of its inner arm 34 under the shoulder on the scar.

so that. the parts will be in position to tit-0" the next shot. after the breech block has returned to its forward firing position.

\Vhile the firing mechanism carried by thei breech block described hereinbefore is para ticularly adapted for use with the improved trigger mechanism and impulse generating and transmitting nnit,'it will be understood that it. can also be advantageously used, with other types of trigger mechanisms.

Furthermore, while tbe'threc units described form a particularly etlicicnt firing control for automatic machine guns when used together. it. will he understood that the trigger mechanism could readily be adapted for use with other impulse. transmitting means. such as hydraulic or elcctrical transmitting means. and the particular me chanical transmitting means might he used with other types of trigger mechanisms.

What I claim and desire to secure by Letter Patent is:

In a firing control for an automatic machine gun. the combination of a breech casing and a trigger mechanism unit carried by said casing and constituting a part additional thereto, the said unit comprising means whereby the gun to which it is applied may he fired. at will. either in s vncln'm nism with a rapidly rotating element or antomatically at the normal rate of fire of the gun.

2. In a firing control for an automatic machine gun. the combination of'a breech eas ing. a trigger mechanism unit carried by son] casing and constitutim a part additional thereto. a firing member in said casinjg. movable means carried by said unit and erttending into said casing for controlling said firing member. and means whereby said n rovable means may he operated. at will. either manually or in synchrynism with a rapidly rotating member.

3. In a firing control 3401" an automatic gun adapted to he mounted on an aircraft to fire through the 'tield swept by the propeller blades. a tiring member. a/trigger mechanism unit detachably secured to the gun. and means for controlling said tiring member from said trigger mcch'anism unit. to fire the gun, at will. eithcr in s \'nchronism with the aircraft: propeller or autonmtically at the normal rate of tire of the gun.

4. In a firing control for an automatic machine gun adapted to fire in synchronism with the rotation of the pro )tlltl of an aircraft, the combination of a breach casing. a

detachable frame carrying trigger mechar.

nism supported by said casing, a firi member controlled by said trigger mechmlsrn. said "lllOtfllfllllSlll t'nlllpl'lfimg manual mean.

and synchronized means for rendering said tiring member operative, and means whereby said synchronized means may he. at will, rendered operative or ino uu'ative.

. t l Ill a tiring control for an automatic machine gun, thecombination of a breech casing. a-tiring member within said casing. a trigger mechanism frame removahly. supported by said casing. a movable clement carried b v said frame and cxtelning into said casing to control said tiring member, and mean wlu-relrv said clcnu-ut may he. at.

will. operated imumallvor in symrhronism with a rapidly rotating member.

6. In atiring control for an automatic machine gun adapted to be mounted on an aircraft to tire through the ticld swept by the n'opeller blades. the combination of a ln'eecl1-casing.- a brecch block reciprocablc within'saidcasing. a tiring member and releasing. means tln-rel'or carried by said breeclrbl clt. a s vncln'oni'/.ed trigger and a numinll -Qpcrated trigger on said casing, andnfor qperalivetr cunln't'llllg cltln'l of said triggers with said rcleasing means whereby thegnn may he. at will. tired syncltrt-mou ly or aulonmticallv at its normal rate of tire.

- 7..In a tire control for an automatic machine gun adapted to be mounted on an air-. craft and bred through the ticld swept b v the propeller blades. the combination of means for generating impulses in svnclnoltlSl'iIHYlill the rotation of the prolwllcr. impulse transmitting means actuated b said generating means. a tiring member. and a trigger mechanism on the gun (meratirely associated with said transmitting means and with said tiring member. said trigger mc h ani' m comprising means for; at will. rendering said transmitting..nn-ans inoperative aml thus permitting the gun to be tired automati- V cally at its normal rate and also comprising manually controller. nn-ans for causing the automatic operation of said tiring member.

8. In a tire control for an automatic machine gun. the combination of a longitudinally reciprm-ating breech block, a tiring controlling member after the firing of a shot huts-aid manual operating means being at all times in operative relation to said controlling member. 9. In a thing control foran automatic l to ' member carried by said breech block. a memhen having pivotal as well as endwise move- I 2.; block therein:

machine gun adapted to be mountedlo'n an means and also" between aircraft to fire through the field swept by "said connecting means.

the propeller blades, the combination of 13.. In a firing control for an automatic breech casing,- a breech block mounted for 'tirearm the combination of a firing member longitudinal reciprocating movement in-saidii meims'forholding said member in cocked casing, a spring-actuated firing pin on saidiyposition 'rpeans for releasing breech block. means for holding said pinliuf means cocked position, mean; for actuatinga'said pooh holding means con'iprising amanually ope said element and ,gomprising a lever having, a commovement and an element for, impart ng'morement: to said lever about an ated trigger, a synchronized trigger anda axis parallel with the firearm axis to thereby ever operzi'tively connecting said trigger release said holding means to, fire a shot, with said holding meansgsaid connecting and a longitudinally reciprocating member lever having endwiso as well as pivotal in-ore,- fadnpted to impart another niorement to said llnent, and cam means on said breech-block) "leverto breath the connection between said ereby said lever is movedendwise after ,lever.antl said element, vheroby said element firing a shot to break its operative conneeisinoperittire to fire-another shot until it is tion with the s nchronizedtriggcr luit..with-."" turned again to its original position. out breaking tie connection bctnee-nit-aml f li lll alfirin control for an automatic -the 11mnually-opcrated triplex. 5 f-lilea-rin, the com inationof a firing; member, IOIIn a firing control for an automatic means for holding said member in cocked an adapted to he means for releasing said holding mounted on an aircraft to position. I re through the field swep tgbyythe propeller means comprising a lever having endn'ise movement ns'well as pivotalmovement about Y blades. the combination \vti'tlrthelh' 1 1 nn axis parallel with the firearm axis. a triging of the gun and-the reciprocati of'a'firing'fmechanisl 1;. Lied, gel for wringing said lever about its pivot by the breech block, a trigger-Carrie heathen-ll rcleasingr aid holding means to tire casing independently of the b|'ce.z-h;lil iek and-i'u shot, and a longitiutinalty reciprocating movable into and out of a position for, cansmemberadaptedto recoil after the firing of ing firing when the breech block-and airin allot and to break the connection between no mechanism are in theirtorw-ard positions impulse transmitting means for moring the said trigger is in- .trigger into and out. of the said p'ositi .nrin.'= bpcratne to tire another shot until it is :cs \-'nchronism with the rotation of the propel}, turned to'its originld position. leizand a spring-actuated element having a; 1 5. In -'a tiring control for an automatic 3- cam surf: -e for moving the trigger to-iind V chine gunaldapted to'be mounted on an holding it in a position at which the trans-" il'vtl'aft' ilndl ill'tt through the ticld swept mittingineuus is inoperatirc'tomore.itggthe l)y-'the propeller blades, the combination of said element being manually movable to ren ,abl'e'cci caring, tr longitiulinally reciprolease the trigger from the lust said position. eating bi'eec lrbloclga tiring member. means W 11. In a fire control for an ai'itomaticimafor.controlling. l t'fir'fl Of' Sa d firing chine gun adapted to be mountedon an air In nibeni c'omprising.,a lever mounted to craft to tire through tlicwfield-sweptb v, tl.ien' n',a,ve1 n ver e plane and to propeller blades. the combination of afiying I I; also a limited endwi-re movement, an member, mraus fou lloldlng said firingIrmem-j tm l t duu'. Y 1 flit 5 ber in cocked position, an;lement'adapted J'Qtflfltlfl, 'ot thenlrcraft propeller to swing or oscillate .in svnehronisiu with the rota aid lerclabolit its pivot to release the firing, tion of the propeller of th i ft, means me nlnn; and-a cam surface on said breech is mored endwise operatively connecting said holding means, '-'l l y id lever and. means for rendering after the t ring of-a shot to break the operererwond\\'ise whereby and aid clement. I I. p

the same connection inoperative comprising atlve ;connect1on between the same and illtl a manually-coutrolled'part and a longitudif flf em lfi c j 'l fltle gram returned nally reciprocating member. torts inoperative posltion.

12,111 a fire control for an automatic not-q li -In; ni filfin g c ntrnl to an automatic chine gun adapted to be mounted on an air; ffl 'ncflgfl ut "the'fit n'lbiuation of n breech craft tofire thronglnthe .liel d swept hy' 'tl1 e ar mg."uhrmg,member with n said casing.

propeller blades, the-combination {if-it fir a frame n einber mounted on the ootsnle of mg men iber, means for holding said firing aid-eas ng jurhunted longitudinal movel -4n 1embcr in cocked position. aniclement niovmentgiar e ement able in synchronisin ivith thejrotation kiftlio-{to tihe ax isof the gun carried by, said frame o aircraft propeller,means for so inovingisaid -member',"-and means opcratively ronnerting element moans operatively connecting said said firing member with said element for all holding means and said element. and means positions of said frzune member within the for at will. breaking the operative conneclim irts of its movement. ti' o'nbetween said element andisaid movin firing control for an illltO lmlit Said holding fnid le've'n and said trigger by'moving then 'ovablc in a plane parallel {moving said controlling means mduntcd on."

said movabic part, saidjcontrollingmeans;

A and said mo'ring means being so constructed and arranged as to u'laiutain their copper, -.at 1\'e relation for all operative Ijtiflld parts of the frame.

positions of, l I

18.; la a firing control 'tor au'antomatlc machine gun adaptcdto he. fixedly admitted on an aircraft to tire throagh theliehlsu'ept by the propeller blades, tirmgmechanism on the gun comprising an element mounted on a .frame part having limited longitudinal, movement relative to thefgun, an impulse generator driven from the aircraft. motor, mechanical means for trau mittiug'impuhes from said generator to said elenu-nt, andv rigid spacing means connecting said frame, pa rt to said impulse generator. whereby the. timeof tiring of the gun is not: atlectedby. longitudinal vibrations thereof.- 5

' 19. la a firing 'controli't'or an automatic machine gun, the combination of a breech casing. a breech block having longitudinal movement within said eating, an element of,- the tiring mechanism carried by said breech block. an actuatorfor said element, mount ed on a part having limited movement:Ions: gitudinally of said casing an impulse gene-- rator. means comprising a push rod connect-i iug said impulse generator and actuator,- and, spacing means whereby Said movablepart is] kept at acoustant distance from said impulse generator thtrob insuri :ing of the tiring of the 'gun.

'2". In a firing control for an automatic machine gun, trigger mechanism, an' impulse generator, and mccl tanieal means [or operating said trigger mechanism in rt."

spouse to the impulses transmitted from said Tgcncrator. said means comprising a spacing tube between said generator amt the gun, a

gun. trigger rod within the tube and of-smaller diameter than the bore of said tube for transmitting the impulses from said generator to the trigger mechanism. supporting said rod within said tube comprising bearing bushings lrranged at interrulsin said tube. p y

:21. In a tiring control for an automutil; mechanism, an impulse genera: tor. mechanical means for operating said" tt'igge" mechanism in response to the innpulses transmitted from said generator, amt means comprising a spacing tube having one, end thereof adjacent to said generator and; a rod guided in'said spacing tube and adapt-,-

05 .ed to transmit impulses from said generator 11g the proper tuuand means for guiding and ,nism comprising to said triggermecbauism, and means for uut'oinatica'llv withdrawing said rod from ';(|pe1':iti'\'e relation with the impulse generaltor-whcn the .s \'lu'hrunlzed tire is stopped.

and tieother to the rod.

Including a spriug tending to hold the mechanism n ts-inoperat ve [Nn-ittluh, an impulse generator, im-chamca'l means tor operating said trigger mechanism ,in opposition .to the said springin respouseto the impulses transmitted from said generator, said means said last-named means comprisin -a helical.

221 In'a'liriug'control for an automatic gun, the combination of trigger mechaulsm,

romprisin" a spacing tube haviug'one end thereof it! jacent to said generator and a rod guided m said spacing tube and adapted to transmit impulses from said generator to said trigger mechanism, and means i'or autolnatn-ally witlldrawlng said rod from operative relation with the impulse generator when the trigger mechanism is manually moved toils mopm'atire position, said lastfnamcd means comprising a'helical spri n snrrmnnliug' said rod and baring one end operatively secured to the spacing tube and the other to the rod. 4

23.11111 tiring control' for an automatic "mm-him. gun adapted to be mounted on an aircraft to tire througb-the lield swept. by the propcller bladcs, the combination with the breech casing of the gun, a trigger mechanism frame carried by the said casing, a tiring member and an element for controlling said member 'carried by said frame, of means for actuating said trigger mechanism comprising a cam shaft rotating in svncbronism with the rotation of the propeller of the aircraft1,.a pair of push rods arranged at an angle to each other, one of said rods extendin substantially parallel to said ele-' ment am the other of said rods having its end l'tJl'lUlG from theti'ri-t-namcd rod and in operative relation with the cam shaft, a rocker operatirely connecting the adjacent ends of the rods, a supportfor the rocker, and spacing means betwen' the actuating means and the rocker support and between the rocker support and the trigger mecha- ,i'tisnl.

24. Ina firing control for an automatic machine gun adapted to be mounted on an aircraft to tire through the tield swept by the propeller blades, the combination with ,t'ho l)1'eecl 1'casi||g of the gun, a trigger mechanism frame carried by the said casing, a bring member and an element for controlfiling said member carried by said frame,

of means for actuating said trigger mechaa cam shalt rotating in synchronism with the rotation of the pro- ;peller of the aircraft, a pair arranged at an angle to-each other, one cl tit) llltl of push rods liitl said rods extending substantially parallel to the gun and having its rear end inoperative; element and the other of said rods having its end remote-from the first-nanuul rod and, in operative"relationwith the cam shaft, a rocker operatively' connecting the. adjacent ends of the rods, a v support for the rocker. and two tubes enclosthe said relation to said ing and guiding the respective rods,

tubes serving as spacing means between the actuating means and the rocker su port and between the rocker support and t e trigger mechanism.

25. In a firing control for an automatic machine gun adapted to be mounted on an aircraft to fire through the field swept by the propeller'blades. the combination with the breech extending substantially parallel to said ele- ,ment and the other of said rods having its ends remote from the first-named rod and inoperative relation with the cam shaft, a rocker operatively connecting the'adjacent ends of the rods. a support for said rocker, and spacing tubes for guiding the said rods,

the adjacent ends of the said spacing tubesbeing adjustably secured to saidsupport to permit rotary as well-as-endwise adjustment of the said tubes relatively to the said sup- Jort.

l 26. In a firing control for an automatic machine gun. an impulse transmitting unit, a trigger mechanism unit on the gun comprising a fixed part and a movable part, and means whereby said impulse transmitting unit may, atflwill, be readily connected or disconnected from themcvahle part of.the

' trigger mechanism unit, said means comprising a spring-actuated element on one of said units adapted to interlock' with the other unit.

27. In a firing control for an automatic machine gun adapted to be mounted on an aircraft to'fire through the field swept by the propeller blades, the combination o't a firing member, a trigger mechanism -unit' mounted on the gun and comprising a frame part having limited longitudinal movement relative to the gun, an element 'movably mounted on said part and operatively con nected with said tiring member, an impulse.

generator spaced longitudinally from said' trigger mechamsm frame and driven in' ing a constant distance between said frame part and said generator, mechanical means. r

(spacing means, and 'a" rea casing of the gun. a trigger mechanism frame carried by the said casmgfa firing member and an element for control-' said frame part, whereby a gun connected with said impulse transmission means may be. readily dismounted and another stituted therefor without necessitating any change in the adjustments of said transmitting means.

28. In a firing control for an automatic machine gun,- an impulse transmitting rod, a tube for guidin said rod, a trigger mechanism frame on t e gun having a movable part and carrying an element adapted to be actuated by the impulses transmitted by said rod, and means whereby said tube may, at will, be readily. connected or disconnected from the movable part of the trigger mechanism frame, said means comprising a springactuated locking member.

29. In a. firing control for an automatic machine gun adapted to be mounted on an aircraft to fire through the field swept by the propeller blades, a trigger mechanism unit having a movable part attached to the gun, an impulse transmitting unit having a portion thereof extending substantially parallel to the gun, and adapted tobe detachahly connected to said movable part of the trigger mechanism unit, whereby a gun with a trigger mechanism unit thereon may be readily dismounted or mounted in posi-' tion on the aircraft without disturbin the adjustments of unit. 30. In a firing mechanism for an automatic machine gun, the combination of a breech block, a spring-actuated firing pin having a beveled cocking shoulder, a vertically sliding sear having a correspondingly beveled shoulder for engagement with said cocking shoulder, and means for preventing lowering movement of the 'sear when the firi ng pin is held cocked, said means com ris- 1ng a sear catch pivoted on the breech h ock and having a shoulder thereon for engagement with a corresponding shoulder on the sear. 31 In a firing mechanism for anautomatlc machine gun, the combinaton of a breech block, a spring-actuated firing pin carried by said. breech block and having an inclinedcocking shoulder, a sear also carried by-said breech block and having a correspondingly inclined shoulder for engagement with said cocking. shoulder, said inclined shoulders and said firing pin spring tending to move the sear to inoperative .position, and means normally preventing synchromsm with the rotation of.the air'-' craft propeller, spacing means for maintainsuch. movement of the sear comprising a lever mounted on the breech block and o ieratively engaging said sear.

v32.-In a firing mechanism for an auto- 11 subthe impulse transmitting i'mohiue' gun, Hus combination of :1 ch 'blbck; a spring-actuatgd firing pin ied thereby, and 'havin an in 'ned inp; shoulder, a sear mova 1a ,to bring a ondingly inclined shoulder tlie'rgon e path'of said cocking shoulddr, and us forlqckingthe searm such position nst the action of the firing pin'spring,

having integraf trunnions fitting i'n correspondmg sea'ts on the breech block.

. i This specification signed this 2nd day uf July, A. .1). 1924.

JOHN M. BROWNING.

V ornlrrrlosre biig anbcnon- I Patent No; {stages-1 i i i Gt-8mm, it), 1921, to

l Joan M. mm.

It is hereby certified that the above numbered patent was erroneously issued to John Browning, Executor of theEstate of said John M. Browning, Deceased,

whereas said Letters Patent should have been issued to John'Browning, Administrator of the Estate of saidlohn M. Browning; Deceased. 'es shown by the records of assignments in th is ofiice; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 7th day ot' June, A 0. 1927.

v I v Mi). Moore, Seal. 1 Acting Commissioner ,0! Patents. 

